A high-strength insulating hyperbranched polyethylene elastomer material and preparation method thereof

Abstract

The invention discloses a high-strength insulating hyperbranched polyethylene elastomer material and a preparation method thereof. The raw material components of the high-strength insulating hyperbranched polyethylene elastomer material of the invention include: 95-100 parts of hyperbranched polyethylene elastomer, 0.5-1.5 parts of covalent triazine framework, and 3-5 parts of antioxidant, wherein the branching degree of the hyperbranched polyethylene is 50-130 branches / 1000 carbons, the weight average molecular weight is 66,000-534,000, and the Mooney viscosity ML (1+4) is 125 o C is 66 to 78. The mechanical strength of the hyperbranched polyethylene elastomer to which the covalent triazine framework is added as a reinforcing agent is significantly improved, and the insulation performance thereof can be maintained at the original level.

Description

Technical Field

[0001] The invention belongs to the technical field of elastomer materials, and in particular relates to a high-strength insulating hyperbranched polyethylene elastomer material and a preparation method thereof. Background Art

[0002] Hyperbranched polyethylene elastomer (HBPE) is a polyolefin elastomer directly prepared by ethylene homopolymerization. Compared with conventional polyolefin elastomers obtained by copolymerization of ethylene and α-olefins, HBPE has a simple production process, low production cost, and excellent comprehensive performance. It is a new type of polyolefin material with a new structure, which gives polyolefin materials new functions and uses.

[0003] Covalent triazine frameworks (CTFs) are organic porous materials constructed with irreversible triazine bonds as connecting units. Compared with covalent organic frameworks (COFs) connected by dynamic covalent bonds such as imines and borate esters, there are no weak bonds in the CTFs structure, which gives them excellent chemical and thermal stability. In addition, the triazine bonds give CTFs a rich nitrogen content, which makes them have excellent heteroatom effects and have great application potential in the fields of photo / electrocatalysis, energy storage and conversion, and pollutant removal.

[0004] The mechanical strength of elastomeric materials has always been a performance indicator that people generally pay attention to. Carbon black, as a classic reinforcing agent, is widely used in elastomeric materials. However, as a good conductive and heat transfer material, the addition of a large amount of carbon black will affect the original insulation and thermal insulation properties of the elastomeric material. Based on this, the present application proposes to use insulating and thermally insulating CTFs as a reinforcing agent to replace traditional carbon black, which will improve the mechanical strength of the elastomeric material without affecting the insulation and thermal insulation properties of the elastomeric material. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high-strength insulating hyperbranched polyethylene elastomer material and a preparation method thereof.

[0006] The invention provides a high-strength insulating hyperbranched polyethylene elastomer material. The raw materials contained in the material are as follows, measured by weight: 95-100 parts of a hyperbranched polyethylene elastomer, 0.5-1.5 parts of a covalent triazine framework, and 3-5 parts of an antioxidant.

[0007] Furthermore, the hyperbranched polyethylene elastomer is obtained by catalytic polymerization of ethylene monomer in the presence of a nickel catalyst and a co-catalyst.

[0008] Furthermore, the covalent triazine framework is obtained by reacting terephthalonitrile and trifluoromethanesulfonic acid in a quartz glass tube.

[0009] Furthermore, the preparation method of the covalent triazine framework includes keeping the temperature at 240-260° C. for 20-24 hours.

[0010] Furthermore, the antioxidant comprises one or more of antioxidant 168, antioxidant 1010, antioxidant 1076 or antioxidant DLTDP.

[0011] The present invention also provides a method for preparing the high-strength insulating hyperbranched polyethylene elastomer material, comprising the following steps:

[0012] (1) Adding hyperbranched polyethylene elastomer, covalent triazine framework and antioxidant into a mixer;

[0013] (2) Melt mixing at a speed of 30 to 50 rpm and a temperature of 180 to 200°C for 3 to 15 minutes.

[0014] Furthermore, in the melt mixing step, the mixing time is 10 minutes.

[0015] Furthermore, the hyperbranched polyethylene elastomer has a branching degree of 50-130 branches / 1000 carbons and a weight average molecular weight of 66,000-534,000.

[0016] Furthermore, the added amount of the covalent triazine framework is 1.0 to 1.2 parts.

[0017] Furthermore, the volume resistivity of the high-strength insulating hyperbranched polyethylene elastomer material is maintained at 1×10 17 Ω.cm -1 above.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. Hyperbranched polyethylene elastomer (HBPE), as a homopolymer of ethylene, exhibits rubber elasticity at room temperature and has the characteristics of low density, high elasticity, aging resistance, low temperature resistance and easy processing. In addition, its production process is simple and the production cost is low, which is suitable for large-scale industrial production.

[0020] 2. As an organic porous material, covalent triazine framework (CTF) has a large specific surface area and is an insulating material. As a reinforcing agent, only a small amount of it can significantly improve the mechanical properties of HBPE. And as an insulating material, its addition does not change the conductivity of HBPE, and the blended material still maintains excellent insulation properties. DETAILED DESCRIPTION

[0021] The following examples are given to further illustrate the present invention, but are not intended to limit the scope of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the content of the invention still fall within the scope of protection of the present invention.

[0022] The present application provides a high-strength insulating hyperbranched polyethylene elastomer material. The raw material components of the high-strength insulating hyperbranched polyethylene elastomer material (by weight) include: 95 to 100 parts of a hyperbranched polyethylene elastomer, 0.5 to 1.5 parts of a covalent triazine framework, and 3 to 5 parts of an antioxidant.

[0023] A further technical solution is that the preparation scheme of the covalent triazine framework is:

[0024] Add terephthalonitrile and trifluoromethanesulfonic acid into a quartz glass tube, evacuate the quartz glass tube, seal it with a flame, and heat it for 4 to 5 minutes. o The heating rate was 240-260 °C / min in a muffle furnace. o C, and keep warm for 20-24 h. Then the quartz glass tube is cooled to room temperature by itself, cooled twice with liquid nitrogen and opened. The obtained powder is ultrasonically washed with 2 M dilute ammonia water, ethanol and dichloromethane in turn, and the obtained product is heated at 80-90 o C and vacuum dried for 12-16 h to obtain a covalent triazine framework gray-green powder.

[0025] A further technical solution is that the highly branched polyethylene elastomer is obtained by catalytic polymerization of ethylene monomer under the action of a nickel catalyst and a co-catalyst, and has a branching degree of 50-130 branches / 1000 carbons, a weight average molecular weight of 66,000 to 534,000, and a Mooney viscosity ML (1+4) of 125 o C is 66~78.

[0026] A further solution is that the degree of branching of the highly branched polyethylene elastomer is 50-130 branches / 1000 carbons, the methyl content is 61.0-66.7 mol%, the ethyl content is 6.8-11.3 mol%, the propyl content is 4.5-5.8 mol%, the butyl content is 3.0-5.3 mol%, the pentyl content is 2.8-5.2 mol%, and the branch content with carbon number ≥6 is 12.5-14.8 mol%.

[0027] In a further embodiment, the antioxidant comprises one or more of antioxidant 168, antioxidant 1010, antioxidant 1076 or antioxidant DLTDP.

[0028] The present application also provides a method for preparing the above-mentioned high-strength insulating hyperbranched polyethylene elastomer material, and the steps of the processing method include the following:

[0029] Adding a hyperbranched polyethylene elastomer, a covalent triazine framework, and an antioxidant into a mixer;

[0030] At a speed of 30-50 rpm, 180-200 o C, and melt-mixed for 3 to 15 minutes to obtain a high-strength insulating hyperbranched polyethylene elastomer material.

[0031] In the above preparation process, if the rotation speed is too low, the processing temperature is too low, and the melt mixing time is too short, the softening temperature of the material will not be reached, resulting in excessive torque during the processing, increased energy consumption, insufficient filler mixing, and affected dispersion performance, thereby affecting the mechanical strength and insulation properties of the material; if the rotation speed is too high, the processing temperature is too high, and the melt mixing time is too long, the material will be partially degraded during the processing, thereby significantly reducing the mechanical strength of the material.

[0032] Embodiment 1:

[0033] Preparation of covalent triazine framework

[0034] Add terephthalonitrile (1.28 g, 10 mmol) and trifluoromethanesulfonic acid (880 μL, 10 mmol) into a quartz glass tube (5 × 20 cm). Evacuate the quartz glass tube, seal it with a flame, and heat it for 4 to 5 min. o The heating rate was 240-260 °C / min in a muffle furnace. o C, and keep warm for 20-24 h. Then the quartz glass tube is cooled to room temperature by itself, cooled twice with liquid nitrogen and opened. The obtained powder is ultrasonically washed with 2 M dilute ammonia water, ethanol and dichloromethane in turn, and the obtained product is heated at 80-90 o C and vacuum dried for 12-16 h to obtain 1.05 g of gray-green powder with a yield of 82.03%.

[0035] Preparation of high-strength insulating hyperbranched polyethylene elastomer materials

[0036] The raw materials include: 100 parts of hyperbranched polyethylene elastomer, 0.5 parts of covalent triazine framework, and 3 parts of antioxidant 1010.

[0037] The processing method of the high-strength insulating hyperbranched polyethylene elastomer material specifically comprises the following steps:

[0038] (1) mixing a hyperbranched polyethylene elastomer, a covalent triazine framework, and an antioxidant in a mixer;

[0039] (2) At a speed of 30 to 50 rpm, 180 to 200 o C, and melt-mixed for 3 to 15 minutes to obtain a high-strength insulating hyperbranched polyethylene elastomer material.

[0040] Embodiment 2:

[0041] The covalent triazine framework was prepared according to Example 1

[0042] Preparation of high-strength insulating hyperbranched polyethylene elastomer materials

[0043] The raw materials include: 100 parts of hyperbranched polyethylene elastomer, 1 part of covalent triazine framework, and 3 parts of antioxidant 1010.

[0044] The processing method of the high-strength insulating hyperbranched polyethylene elastomer material specifically comprises the following steps:

[0045] (1) mixing a hyperbranched polyethylene elastomer, a covalent triazine framework, and an antioxidant in a mixer;

[0046] (2) At a speed of 30 to 50 rpm, 180 to 200 o C, and melt-mixed for 3 to 15 minutes to obtain a high-strength insulating hyperbranched polyethylene elastomer material.

[0047] Embodiment 3:

[0048] The covalent triazine framework was prepared according to Example 1

[0049] Preparation of high-strength insulating hyperbranched polyethylene elastomer materials

[0050] The raw materials include: 100 parts of hyperbranched polyethylene elastomer, 1.5 parts of covalent triazine framework, and 3 parts of antioxidant 1010.

[0051] The processing method of the high-strength insulating hyperbranched polyethylene elastomer material specifically comprises the following steps:

[0052] (1) mixing a hyperbranched polyethylene elastomer, a covalent triazine framework, and an antioxidant in a mixer;

[0053] (2) At a speed of 30 to 50 rpm, 180 to 200 o C, and melt-mixed for 3 to 15 minutes to obtain a high-strength insulating hyperbranched polyethylene elastomer material.

[0054] Comparative Example 1:

[0055] Preparation of Hyperbranched Polyethylene Elastomer Materials

[0056] The raw materials include: 100 parts of hyperbranched polyethylene elastomer and 1010 3 parts of antioxidant.

[0057] The processing method of the hyperbranched polyethylene elastomer material specifically comprises the following steps:

[0058] (1) Mixing a hyperbranched polyethylene elastomer and an antioxidant in a mixer;

[0059] (2) At a speed of 30 to 50 rpm, 180 to 200 o C, and melt-mixed for 3 to 15 minutes to obtain a hyperbranched polyethylene elastomer material.

[0060] Comparative Example 2:

[0061] Preparation of carbon black reinforced hyperbranched polyethylene elastomer

[0062] The raw materials include: 100 parts of hyperbranched polyethylene elastomer, 30 parts of carbon black N330, and 3 parts of antioxidant 1010.

[0063] The processing method of the carbon black reinforced hyperbranched polyethylene elastomer material specifically comprises the following steps:

[0064] (1) Mixing a hyperbranched polyethylene elastomer, carbon black, and an antioxidant in a mixer;

[0065] (2) At a speed of 30 to 50 rpm, 180 to 200 o C and melt-mixed for 3 to 15 minutes to obtain a carbon black reinforced hyperbranched polyethylene elastomer material.

[0066] Table 1 Performance comparison of hyperbranched polyethylene elastomer materials obtained in the examples and comparative examples

[0067]

[0068] By comparing Example 1, Example 2, and Example 3 with Comparative Example 1, it is found that the addition of a covalent triazine framework can effectively enhance the mechanical properties of a hyperbranched polyethylene elastomer. This is because the covalent triazine framework has a large specific surface area and can effectively adsorb the molecular chains of the elastomer. The adsorbed molecular chains will slide and elongate under stress, thereby increasing the mechanical strength of the hyperbranched polyethylene elastomer to 135% to 150% of the original. And as the amount of covalent triazine framework added increases, the mechanical strength continues to increase, but the elongation at break decreases significantly. This may be because as the amount of filler added increases, a filler agglomeration effect is generated, thereby generating a stress concentration area, which affects the mechanical properties of the hyperbranched polyethylene elastomer material. Comprehensive comparison shows that the high-strength insulating hyperbranched polyethylene elastomer material obtained by adding only 1 mass fraction of a covalent triazine framework has the best mechanical properties.

[0069] By comparing Example 1, Example 2, and Example 3 with Comparative Example 2, it is found that the mechanical strength of the hyperbranched polyethylene elastomer material with only 1 mass component of the covalent triazine framework added is equivalent to that of the hyperbranched polyethylene elastomer material with 40 mass components of carbon black added, and its volume resistivity can still be maintained at the original order of magnitude, while the volume resistivity of the carbon black-reinforced hyperbranched polyethylene elastomer material is reduced by 9 orders of magnitude compared with the original, which has a significant effect on the insulation properties of the elastomer material.

[0070] In summary, as a porous organic polymer, the covalent triazine framework can significantly improve the mechanical strength of the hyperbranched polyethylene elastomer material with only a small amount of addition, and will not change the insulation properties of the elastomer itself. As an insulating reinforcing filler, the covalent triazine framework has broad application prospects in the field of elastomers.

[0071] Although the present application has been described above with reference to specific embodiments, various modifications may be made thereto and may be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no conflict, the various features in the specific embodiments disclosed in the present application may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A high-strength insulating hyperbranched polyethylene elastomer material, characterized in that: The raw materials contained in the invention are as follows, in parts by weight: 95-100 parts of hyperbranched polyethylene elastomer, 0.5-1.5 parts of covalent triazine framework, and 3-5 parts of antioxidant; The preparation process of the covalent triazine framework is as follows: Add terephthalonitrile and trifluoromethanesulfonic acid into a quartz glass tube, evacuate the quartz glass tube, seal it with a flame, and heat it for 4 to 5 minutes. o The heating rate was 240-260 °C / min in a muffle furnace. o C, keep warm for 20-24 h; after the quartz glass tube is cooled to room temperature, it is cooled twice with liquid nitrogen and then opened; the obtained powder is ultrasonically washed with 2 M dilute ammonia water, ethanol and dichloromethane in turn, and the obtained product is heated at 80-90 o C and vacuum dried for 12-16 h to obtain a covalent triazine framework gray-green powder.

2. The high-strength insulating hyperbranched polyethylene elastomer material according to claim 1, characterized in that: The hyperbranched polyethylene elastomer is obtained by catalytic polymerization of ethylene monomer under the action of a nickel catalyst and a co-catalyst.

3. The high-strength insulating hyperbranched polyethylene elastomer material according to claim 1, characterized in that: The antioxidant comprises one or more of antioxidant 168, antioxidant 1010, antioxidant 1076 or antioxidant DLTDP.

4. A method for preparing the high-strength insulating hyperbranched polyethylene elastomer material according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) Adding hyperbranched polyethylene elastomer, covalent triazine framework and antioxidant into a mixer; (2) Melt mixing at a speed of 30 to 50 rpm and a temperature of 180 to 200°C for 3 to 15 minutes; The preparation process of the covalent triazine framework is as follows: Add terephthalonitrile and trifluoromethanesulfonic acid into a quartz glass tube, evacuate the quartz glass tube, seal it with a flame, and heat it for 4 to 5 minutes. o The heating rate was 240-260 °C / min in a muffle furnace. o C, keep warm for 20-24 h; after the quartz glass tube is cooled to room temperature, it is cooled twice with liquid nitrogen and then opened; the obtained powder is ultrasonically washed with 2 M dilute ammonia water, ethanol and dichloromethane in turn, and the obtained product is heated at 80-90 o C and vacuum dried for 12-16 h to obtain a covalent triazine framework gray-green powder.

5. The method according to claim 4, characterized in that In the step of melt mixing, the mixing time is 10 minutes.

6. The method according to claim 4 or 5, characterized in that: The hyperbranched polyethylene elastomer has a branching degree of 50-130 branches / 1000 carbons and a weight average molecular weight of 66,000-534,000.

7. The method according to claim 6, characterized in that The added amount of the covalent triazine framework is 1.0 to 1.2 parts.

8. The method according to claim 7, characterized in that The volume resistivity of the high-strength insulating hyperbranched polyethylene elastomer material is maintained at 1×10 17 Ω.cm -1 above.

Images